A woman walks through the snow in the early morning hours in Manhattan's East Village.Getty Images

The feds have opened a criminal investigation into allegations that city employees conspired to paralyze the city during last week’s blizzard by failing to remove the snow, authorities confirmed today.

The probe launched by the Brooklyn US Attorney’s Office comes in response to City Councilman Dan Halloran (R-Queens) revelations to The Post last week that sanitation workers told him they were involved in a work slowdown, sources told The Post.

At the same time, both the Brooklyn and Queens DAs offices have started their own investigations into whether there was a work slowdown.

The Brooklyn US Attorney’s Office is investigating whether there was a conspiracy to cripple parts of the city, according to a source.

The feds are trying to determine whether the plow supervisors conspired to defraud city taxpayers by padding their overtime pay, which could result in mail or wire-fraud charges.

The DAs in both counties, where snow removal was at its worst, are conducting inquiries as well, spokesmen for those offices confirmed to The Post.

Mayor Bloomberg and Sanitation Commissioner John Doherty have denied there was any orchestrated effort to halt the cleanup effort.

Halloran told The Post that he met with three plow workers from the Sanitation Department — and two Department of Transportation supervisors who were on loan — at his office after he was flooded with irate calls from constituents.

The snitches “didn’t want to be identified because they were afraid of retaliation,” Halloran said. “They were told [by supervisors] to take off routes [and] not do the plowing of some of the major arteries in a timely manner. They were told to make the mayor pay for the layoffs, the reductions in rank for the supervisors, shrinking the rolls of the rank-and-file.”

New York’s Strongest used a variety of tactics to drag out the plowing process – and pad overtime checks – which included keeping plows slightly higher than the roadways and skipping over streets along their routes, the sources said.

The snow-removal snitches said they were told to keep their plows off most streets and to wait for orders before attacking the accumulating piles of snow.

They said crews normally would have been more aggressive in com bating a fierce, fast-moving blizzard like the one that barreled in on Sunday and blew out the next morning.

The workers said the work slowdown was the result of growing hostility between the mayor and the workers responsible for clearing the snow.

In the last two years, the agency’s workforce has been slashed by 400 trash haulers and supervisors — down from 6,300 — because of the city’s budget crisis. And, effective tomorrow, 100 department supervisors are to be demoted and their salaries slashed as an added cost-saving move.

Sources said budget cuts were also at the heart of poor planning for the blizzard last weekend. The city broke from its usual routine and did not call in a full complement on Saturday for snow preparations in order to save on added overtime that would have had to be paid for them to work on Christmas Day.

The result was an absolute collapse of New York’s once-vaunted systems of clearing the streets and keeping mass transit moving under the weight of 20 inches of snow.